Enatega Customer Application (App Language)

Is your feature request related to a problem? Please describe.
The application is asking for a specific language to select and when the user does that, the whole application gets reloaded.

Describe the solution you'd like
the application should be able to picked the language the system is already using and make it its default language.

No files, tests, or entry points are named. Start by locating the customer application's language selector and the logic that reloads the application after selection. Done means the app can detect the system language, use it as the default, and the expected language-selection behavior is verified without an unnecessary reload.

Written by the indexing model from the issue text.